Introduce docc documentation and "supported features" #766

Job	Run time
Test (Java) (macos swift:6.1.2 jdk:corretto)	26s
Documentation check (6.1.2, jammy, corretto)	15s
Test (Java) (jammy swift:6.1.2 jdk:corretto)	40s
Test (Swift) (macos swift:6.1.2 jdk:corretto)	39s
Test (Swift) (jammy swift:6.1.2 jdk:corretto)	42s
Sample JavaDependencySampleApp (macos swift:6.1.2 jdk:corretto)	1s
Sample JavaKitSampleApp (macos swift:6.1.2 jdk:corretto)	1s
Sample JavaProbablyPrime (macos swift:6.1.2 jdk:corretto)	1s
Sample SwiftAndJavaJarSampleLib (macos swift:6.1.2 jdk:corretto)	1s
Benchmark (JMH) (jammy swift:6.1.2 jdk:corretto)	36s
Sample JavaSieve (macos swift:6.1.2 jdk:corretto)	1s
Sample JExtractJNISampleApp (macos swift:6.1.2 jdk:corretto)	39s
Sample SwiftKitSampleApp (macos swift:6.1.2 jdk:corretto)	25s
Sample SwiftKitSampleApp (jammy swift:6.1.2 jdk:corretto)	36s
Sample JavaDependencySampleApp (jammy swift:6.1.2 jdk:corretto)	39s
Sample SwiftAndJavaJarSampleLib (jammy swift:6.1.2 jdk:corretto)	38s
Sample JavaKitSampleApp (jammy swift:6.1.2 jdk:corretto)	36s
Sample JavaSieve (jammy swift:6.1.2 jdk:corretto)	37s
Sample JavaProbablyPrime (jammy swift:6.1.2 jdk:corretto)	37s
Sample JExtractJNISampleApp (jammy swift:6.1.2 jdk:corretto)	36s
soundness / Unacceptable language check	3s
soundness / Documentation check	0s
soundness / Broken symlinks check	4s
soundness / YAML lint check	4s
soundness / License headers check	6s
soundness / Shell check	33s
soundness / API breakage check	0s
soundness / Format check	0s
soundness / Python lint check	10s
	9m 46s

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